Every year, the American Psychological Association conducts a survey about stress in the United States. Some of the more common stressors are money, family responsibilities, health-related concerns, and work. To see more sources of stress, and see some generational differences and trends on stress level, see https://www.apa.org/news/press/releases/stress/2018/interactive-graphics.
A modern type of stress comes from overuse and over-reliance on technology. This has been termed technostress and it can have serious harmful effects. For more on how to deal with this, see
https://www.psychologytoday.com/us/blog/prefrontal-nudity/201708/dealing-technostress .